[occi-wg] Typed Link Kind

[Jean Parpaillon]

Hi Boris,

Le vendredi 31 juillet 2015 à 11:48 +0200, Boris Parak a écrit :
> Hi Jean,
> 
> On Fri, Jul 31, 2015 at 10:49 AM, Jean Parpaillon
> <jean.parpaillon at free.fr> wrote:
> > Hi all,
> > With Olivier Barais, in CC, with which I am working on the OCCIware
> > project, we would like to enhance the core specification with a way 
> > to
> > constrain the Category of resources pointed out by occi.core.src 
> > and
> > occi.core.target attributes of a link.
> > 
> > For instance, in the infrastructure extension, while it is 
> > specified
> > (and easily make sense) a NetworkInterface link must be linked to a
> > compute and a network instance, there is no formal way to define 
> > this
> > constraint.
> > 
> > A proposal would be to add new type of Category, sub-type of Kind, 
> > with
> > following attributes:
> > - parent: instantiated as http://schemas.ogf.org/occi/core#link
> > - occi.core.src.type: additional attribute, type category id
> > - occi.core.target.type: additional attribute, type category id
> > 
> > The name of this type of Category could be "TypedLinkKind".
> > 
> > What do you think of this ?
> 
> at first glance, it looks like a reasonable request ... it would
> definitely improve automated validation and modeling in OCCI.
> Especially with previously unknown extensions.
> 
> 'occi.core.target' will be a bit problematic, because it can point
> "outside" the local domain. But we could easily cover that by making
> these attributes optional.
> 
> So, I would consider dropping the TypedLinkKind and include these two
> attributes in the existing Link kind, as optional. That way we get a
> typed link, partially typed link and "legacy" link all-in-one. While
> keeping it all backwards compatible. If the type attribute is 
> present,
> you can use it, if not ... well ... you are out of luck :-)
> 
> As a side note, I would very much like to avoid introducing attribute
> names with matching prefixes:
> 
> occi.core.target = "value"
> occi.core.target.type = "value"
> 
> This makes JSON rendering really difficult. Would you be OK with
> "target_type" & "source_type"?

I would prefer the former one, but I can accept the second one.
BTW, here is the algortihm I use for inserting any dot-separated
attribute name into the JSON tree of attributes, would you be
interested in implementing it into rocci:
https://github.com/erocci/erocci/blob/master/apps/erocci_core/src/rende
ring/occi_renderer_json.erl#L194


> 
> Also, could you, please, include this as a comment here [1], then we
> can discuss it as a part of public comment on OCCI 1.2 and possibly
> include it :-)

Done, last minute before end of comments ;)

> 
> Thanks!
> 
You're welcome.

Jean

> [1] https://redmine.ogf.org/boards/26/topics/429
> 
> > 
> > Regards,
> > --
> > Jean Parpaillon
> > --
> 
> Cheers, Boris
> 
> > Open Source Consultant
> > OW2 Technology Council Chairman
> > Director @ OW2 Consortium
> > OCCIware Strategic Orientation Committee Chairman
> > Research Engineer @ Inria
> > --
> > Phone: +33 6 30 10 92 86
> > im: jean.parpaillon at gmail.com
> > skype: jean.parpaillon
> > linkedin: http://www.linkedin.com/in/jeanparpaillon/en
> > _______________________________________________
> > occi-wg mailing list
> > occi-wg at ogf.org
> > https://www.ogf.org/mailman/listinfo/occi-wg
-- 
Jean Parpaillon
--
Open Source Consultant
OW2 Technology Council Chairman
Director @ OW2 Consortium
OCCIware Strategic Orientation Committee Chairman
Research Engineer @ Inria
--
Phone: +33 6 30 10 92 86
im: jean.parpaillon at gmail.com
skype: jean.parpaillon
linkedin: http://www.linkedin.com/in/jeanparpaillon/en